Low FODMAP French Onion Soup Recipe

This savory, rich Low FODMAP French Onion Soup is made with green leek tops, beef broth, and melted Gruyère, ready in just 45 minutes. The cheese bubbles and browns beautifully over the crisp gluten-free bread, delivering that classic bistro experience. I was surprised how much depth the leek greens provided without any actual onion bulbs.

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The Secret To Getting It Right

I learned that the key to replicating the deep flavor of traditional onion soup lies in patience with the leek greens. You cannot rush the sautéing process; they need time to soften and develop sweetness in the butter, just like regular onions, or they will end up tough.

Another surprise was how essential the splash of dry white wine is for deglazing the pot. It cuts through the richness of the beef broth and adds the acidity that makes this soup taste authentic rather than flat.

Low FODMAP French Onion Soup Ingredients

• For the Soup Base:
• 4 tablespoons unsalted butter
• 4 cups leek tops (green parts only), washed thoroughly and sliced
• 1 bunch scallions (green tops only), chopped
• 1 teaspoon sugar (helps caramelization)
• 2 tablespoons gluten-free all-purpose flour
• ½ cup dry white wine
• 6 cups low FODMAP beef broth
• 1 bay leaf
• 1 sprig fresh thyme
• For the Topping:
• 4 slices gluten-free baguette
• 1 cup Gruyère cheese, grated

How To Make Low FODMAP French Onion Soup

1. Prepare The Greens: Melt the butter in a large pot or Dutch oven over medium heat.
2. Sauté Vegetables: Add the sliced leek tops and scallion tops, cooking for 20 minutes until they are very soft and significantly reduced in volume.
3. Thicken Soup: Sprinkle in the flour and sugar, stirring constantly for 2 minutes to cook out the raw flour taste and encourage browning.
4. Deglaze Pot: Pour in the white wine and scrape any browned bits from the bottom of the pan to release the flavor.
5. Simmer Broth: Add the beef broth, thyme, and bay leaf, then simmer gently for 20 minutes to meld the flavors.
6. Broil Topping: Ladle the soup into oven-safe bowls, top each with a baguette slice and a generous mound of Gruyère cheese, then broil until the cheese is bubbling and golden brown.

Recipe Tips

• Clean leeks well: Dirt likes to hide deep in the green layers of leeks, so wash them thoroughly in a colander after chopping to avoid grit in your soup.
• Check your broth: Many store-bought beef broths contain onion or garlic, so always check the label or use a specific low FODMAP certified brand.
• Don’t skip the wine: The alcohol cooks off, leaving behind a complex acidity that mimics the depth of traditional caramelized onions.

What To Serve With French Onion Soup

Serve this soup alongside a simple green salad with a sharp vinaigrette to cut through the rich, cheesy topping. For a heartier meal, it pairs perfectly with a grilled steak or roasted chicken for a French-inspired dinner menu.

How To Store

Store the soup base in an airtight container in the fridge for up to 3 days, keeping the bread and cheese separate until serving. The soup base freezes beautifully for up to 3 months; just thaw and reheat before adding fresh toppings and broiling.

FAQs

• Is Gruyère cheese low FODMAP? Yes, aged cheeses like Gruyère are naturally low in lactose and are generally considered safe for a low FODMAP diet.
• Can I use chicken broth instead? You can use chicken broth, but beef broth provides the traditional dark color and robust flavor associated with this dish.
• What if I can’t find leek tops? If you don’t have access to leeks, you can use a larger quantity of green scallion tops, though the texture will be slightly less substantial.

Nutrition

• Calories: 450
• Total Fat: 28g
• Saturated Fat: 16g
• Cholesterol: 80mg
• Sodium: 980mg
• Total Carbohydrate: 28g
• Protein: 22g

Try More Recipes:

• Low FODMAP Tom Kha Gai Soup Recipe
• Low FODMAP Tom Yum Soup Recipe
• Low FODMAP Chicken Tortilla Soup Recipe